A series of allegations in Germany and Holland have plunged the Catholic Church into a renewed crisis over how it has dealt with child abuse after it emerged that the Pope's brother ran a renowned choir at the centre of some of the latest claims.

Reports of systematic historical abuse by clergy have surfaced at three schools in the Regensburg diocese in Bavaria. One of them is the much-heralded Regensburger Domspatzen, a thousand-year-old male choir and boarding school, whose choral master for 30 years was the Pope's older brother, Georg Ratzinger.

Monsignor Ratzinger has agreed to testify in any eventual prosecutions - but says that he knew of no abuse. And last night the German Justice Minister, Sabine Leutheusser-Schnarrenberger, joined a growing chorus of politicians in Berlin to criticise the church over its attitude to the investigation, accusing Catholic institutions of a policy of secrecy.